ELECTRONIC COMMUTATION METHOD AND RELATED APPARATUS
2 Assignments
0 Petitions
Accused Products
Abstract
A method and apparatus for electronic commutation of a pulse width modulation (PWM) controlled motor involves temporarily increasing the frequency of one or more PWM drive signals applied to the motor upon the occurrence of an asynchronous commutation event.
-
Citations
32 Claims
-
1-24. -24. (canceled)
-
25. A method of controlling an electronically commutated motor having multiple phase windings by applying PWM drive signals in accordance with a series of commutation states, where a commutation event occurs when a rotor moves from a position associated with one commutation state to a position associated with another commutation state, the method comprising the steps of:
-
(a) applying PWM drive signals at a set frequency on a cyclical basis; (b) detecting a commutation event that is asynchronous with and occurs during an ongoing PWM drive signal cycle at the set frequency; (c) responsive to detection of the asynchronous commutation even in step (b), increasing frequency of PWM drive signals applied during the ongoing PWM drive signal cycle to a frequency above the set frequency in order to reach the end of the ongoing PWM drive signal cycle more quickly than without such a frequency increase. - View Dependent Claims (26, 27, 28, 30)
-
-
31. A motor control system comprising:
-
a motor having multiple phase windings and a movable rotor, the position of the rotor defines multiple commutation states for the phase windings; a sensor arrangement for indicating the occurrence of commutation events when the rotor moves from a position associated with one commutation state to a position associated with another commutation state; and a controller for selectively energizing the phase windings with PWM drive signals, the controller operatively connected with the sensor arrangement and operable, upon occurrence of a commutation event that is asynchronous to an ongoing PWM drive signal of an initial frequency, to increase frequency of the ongoing PWM drive signal to a frequency above the initial frequency in order to reach an end of cycle for the ongoing PWM drive signal more quickly than without such a frequency increase. - View Dependent Claims (32)
-
Specification